Clear Primer

A clear primer developed to soften and prepare all PVC and CPVC plastic pipe and fittings.

Use of this primer will penetrate and soften the joining surfaces more rapidly the cement alone.

Jointing Procedure

1)Prepare the pipe

Before jointing, check that the pipe has been cut square and all the burrs are removed from the inside and outside edge. Remove the sharp edge from the outside and inside of the pipe with a deburring tool. Do not create a large chamfer that will trap a pool of solvent cement. Proper deburring of the pipe end avoids wiping the cement from the inside of the socket when the spigot is inserted to make the joint. Failure to properly deburr may result in inadequate pipe penetration and/or detrimental accumulation of solvent cement at the socket root. Remove all dirt, swarf, and moisture from spigot and socket.

2) Witness mark the pipe

It is essential to be able to determine when the spigot is fully home in the socket. Mark the spigot with a pencil line (‘witness mark’) at a distance equal to the internal depth of the socket. Other marking methods may be used provided that they do not damage or score the pipe.

3) Prepare with priming fluid

Priming is vitally important, as it cleans and primes the PVC surface for the solvent cement’s effective bond. Using protective gloves, dry, degrease and prime the spigot and socket with a lint-free cloth (natural fibres) dampened with priming fluid. Other application techniques that achieve the same purpose may be used.

4) Brush selection

The brush should be large enough to apply the solvent cement to the joint in a maximum of 30 seconds. Approximately one third the pipe diameter is a good guide. Do not use the brush attached to the lid for pipes over DN 100 in size. For large diameter pipes, it may be necessary to decant solvent cement to an open vessel for a large brush to be used. Excess should never be returned to the can.

5) Apply solvent cement

Using a suitably sized brush, apply a thin even coat of solvent cement to the internal surface of the socket first. Solvents will evaporate faster from the exposed spigot than from the socket. Special care should be taken to ensure that excess solvent cement isn’t built up at the back of the socket (pools of solvent will continue to attack the PVC and weaken the pipe). Next apply a similar even coat of solvent cement up to the witness mark on the spigot. Ensure the entire surface is covered. A ‘dry’ patch will not develop a proper bond, even if the mating surface is covered, and may also make it difficult to obtain full insertion. Special consideration should also be given to the temperature in which the joining will be performed. High temperatures may require a marginal increase in application thickness to allow for evaporation before the joint is made. See additional tip #4 below for more detail.

6) Inserting the spigot

Make the joint immediately, in a single movement. Do not stop halfway, since the bond will start to set immediately and it will be almost impossible to insert further. It may aid distribution of the solvent cement to twist the spigot into the socket so that it rotates about a 1/4 turn whilst (not after) inserting. Where this cannot be done, particular attention should be paid to uniform solvent cement application.

7) Push the spigot home

The spigot must be fully inserted to the full depth of the socket. The final 10% of spigot penetration is vital to the interference fit. Mechanical force will be required for larger joints. Be ready in advance. Pipe pullers are commercially available for this purpose. Polyester pipe slings are very useful for gripping a pipe, in order to apply a winch or lever.

8) Hold the joint

Hold the joint against movement and rejection (i.e. pushback) of the spigot for a minimum of 30 seconds. Disturbing the joint during this phase will seriously impair the strength of the joint.

9) Wipe off excess solvent cement

For a neat professional joint, with a clean rag, immediately wipe off excess solvent cement from the outside of the joint.

10) Do not disturb the joint

Once the joint is made, do not disturb it for five minutes or rough handle it for at least one hour. Do not fill the pipe with water for at least one hour after making the last joint. Do not pressurise the line until fully cured.

11) Cure the joint

The process of curing is a function of temperature, humidity and time. Joints cure faster when the humidity is low and the temperature is high. The higher the temperature, the faster the joints will cure. As a guide for pressure applications, at a temperature of 16°C and above, 24 hours should be allowed, at 0°C, 48 hours is necessary.